#!/bin/bash

echo "helloworld!!!"

echo $PATH

echo $USER

echo $HOME

echo $PWD

name="杨杰"

echo $name

readonly age=18

export age

echo $A

echo "=========$0-$9==============="
echo $0
echo $1
echo $2
echo $3
echo "=========$*==============="
echo $*



echo "=========$#==============="
echo $#

echo "=========$@==============="
echo $@

echo "========================"
echo "jack is Superman"
echo "修改dev"